def myrange(start, stop=None, step=1):
    if stop == None:
        return list(range(0, start))
    else:
        return list(range(start, stop, step))


a = int(input("输入开始："))
b = input("输入结束：")
if b == "":
    b = None
else:
    b = int(b)
c = input("输入步长：")
if c == "":
    s = myrange(a, b)
    print(s)
else:
    c = int(c)
    s = myrange(a, b, c)
    print(s)
